Products of Interaction of Antigen-Sensitized Leukocytes and Antigen: Further Characterization of the Mitogenic Factor

Abstract
Studies carried out on mitogenic factor produced by leukocytes from inbred guinea pigs in response to antigenic stimulation indicate that this factor is not transplantation antigen because it produces stimulation of normal leukocytes derived from guinea pigs of the same strain. Its activity was not enhanced by additional antigen. The factor is active on leukocytes derived from several sources, including spleen, lymph nodes, peripheral blood and thymus of outbred guinea pigs, and it is heat-stable.